Cereal aphid flight activity in Hungary and England compared by suction traps

Cereal aphid flight was monitored by 12.2 m suction traps at SzoInok in the middle of the Great Hungarian Plain and at Rothamsted, UK. Flight activities of Rhopalosiphum padi, Metopolophium dirhodum and S. avenae were compared by the cross correlation function (CCF) between Hungary and UK There was significant synchrony between flight activity in Hungary and UK of R. padi, M. dirhodum and S. avenae based on the eight years weekly sample data. The peak flight occurred 1, 3 and 2 weeks later at Rothamsted than at Szolnok for the three species (the CCF values were at -1, week lag, r = 0.854, -3 week lag r = 0.809, -2 week lag r = 0.883, P<0.05 respectively). When the flights in individual years were compared within species and between places the synshrony was lowest for R padi: in 4 years out of 8 and there was no synchrony, in the other years when synchrony occurred the time lag varied between - 1. week and -4 weeks. For M. dirhodum the time lag varied between 1 and -5 weeks, the synchrony was the best for S. avenae the week lag varied between 0 and -3 weeks. Our results show that flight activity of cereal aphids at SzoInok occurs 1-3 weeks earlier than at Rothamsted. The crop season is earlier in Hungary than in England.